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The qualitative X-ray phase analysis of natural and artificial food sweeteners was applied to trace the authenticity of such food additives. The mineral composition of different sweeteners commonly added to foods was studied to estimate their mineral profiles and assess the risk related to the toxic elements intake caused by sweetener consumption. The concentration of twenty elements (Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr, Ti, V, and Zn) was measured using the inductively coupled plasma–optical emission spectroscopy (ICP-OES) method after the representative samples were wet-digested with a concentrated nitric acid and hydrogen peroxide mixture in a closed-vessel microwave-assisted system. Differences between the mineral compositions of the examined sweeteners were statistically evaluated and discussed. The relationships between the concentrations of the elements determined in the analyzed sweeteners were also investigated. The successful application of the X-ray powder diffraction method proved the identity of all investigated sweeteners; all the analyzed products contained the expected sweetening agent. The results of the quantification of all the elements in the examined sweeteners indicated that these products cannot be considered nutritionally dense. Hence, the presence of toxic elements like Cd, Cr, Ni, and Pb distinctly indicates the need to test such products to guarantee their quality and ensure consumer safety.

A fully validated inductively coupled plasma optical emission spectrometry (ICP-OES)–based method combined with a simplified sample preparation procedure for the determination of up to 15 elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn) in caffeinated yerba mate (YM) drinks was proposed. Various “green” treatments (acidification or dilution with a HNO3 solution and direct analysis of untreated YM with or without sonication (US)) that could replace the traditional total sample decomposition before spectrometric measurements were tested and compared. The key selection parameter was the analytical performance of the ICP-OES method obtained with each sample preparation procedure in terms of the precision and the trueness of results and limits of detection (LODs) of elements. It was found that the acidification of YMs with concentrated HNO3 to 5%, supported by US (10 min, room temperature (RT)), provided the best results, i.e., LODs at 0.11–8.5 ng g−1, precision below 5%, and trueness better than 5% (97.0%–105% as recoveries). Eleven YM drinks, commercially available on the Polish market, were analyzed with the proposed method. In addition to the mineral content, the concentration of caffeine in all analyzed YMs was determined and compared. Finally, the studies were completed by determining the bioaccessible fraction of selected elements and caffeine in YMs using in vitro gastrointestinal digestion (GID) in order to evaluate the nutritional value/risk assessment of these drinks. Accordingly, the bioaccessibility of nutritious elements (Ca, Fe, Mg, Mn, Zn) and caffeine was within 40%–59%. Except for Mn, it was established that by drinking daily 1 L of YMs, the recommended dietary intakes (RDIs) of the aforementioned essential elements were covered to a low degree (per serving).

In recent years, there has been an increased interest in products of natural origin. The extraction procedure of bioactive compounds from plant matrices is a crucial step in the development of useful new bioproducts for everyday life. The utilisation of analyses enabling the rapid identification of the presence of a given group of compounds can be helpful in the early stages of the development of new products in order to save time and reduce costs. Within this article, we have presented a comparison of different, accessible methods for the identification of various bioactive compounds, e.g., saponins, carboxylic acids, oils and fats, proteins and amino acids, steroids, and alkaloids in plant-based extracts. Additionally, the multielemental composition of extracts was also examined. The applied methods allowed for confirmation of the presence of biologically active compounds in bio-products obtained by ultrasound-assisted extraction. At a later stage, these procedures should be supplemented by advanced analytical techniques in order to determine the plant chemicals’ content qualitatively and quantitatively.

The aim of this study was to propose a complete approach for macroalgae biomass valorization into products useful for sustainable agriculture and environmental protection. In the first stage, the effects of macroalgal extracts and ZnO NPs (zinc oxide nanoparticles) on the germination and growth of radish were examined. Macroalgal extract was produced from freshwater macroalga, i.e., Cladophora glomerata by ultrasound assisted extraction (UAE). The extract was used to biosynthesize zinc oxide nanoparticles. In germination tests, extracts and solutions of ZnO NPs were applied on paper substrate before sowing. In the second stage, sorption properties of macroalga, post-extraction residue, and ZnO NPs to absorb Cr(III) ions were examined. In the germination tests, the highest values of hypocotyl length (the edible part of radish), i.e., 3.3 and 2.6 cm were obtained for 60 and 80% extract (among the tested concentrations 20, 40, 60, 80, and 100%) and 10 and 50 mg/L NPs, respectively. The highest sorption capacity of Cr(III) ions (344.8 mg/g) was obtained by both macroalga and post-extraction residue at a pH of 5 and initial Cr(III) ions concentration of 200 mg/L. This study proves that macroalgae and products based on them can be applied in both sustainable agriculture and wastewater treatment.

Four procedures based on closed-vessel microwave-assisted wet digestion with different oxidative reagents, including HNO3 (P1), HNO3 + H2O2 (P2), aqua regia (P3) and Lefort aqua regia (P4), for preparation of calcium (Ca)-rich materials prior to determination of total concentrations of Al, Ca, Cd, Fe, Mg and P by inductively coupled optical emission spectrometry (ICP OES) were compared. It was found that digestion with Lefort aqua regia (P4) provided the best results for all examined elements, i.e., precision of 0.30–4.4%, trueness better than 2%, recoveries of added elements between 99.5–101.9%, and limits of detection within 0.08–1.8 ng g−1. Reliability of this procedure was verified by analysis of relevant certified reference materials (CRMs), i.e., Natural Moroccan Phosphate Rock—Phosphorite (BCR-O32). Additionally, selection of appropriate analytical lines for measurements of element concentrations, linear dynamic ranges of calibration curves and matrix effects on the analyte response were extensively investigated. Finally, the selected procedure was successfully applied for routine analysis of other Ca-rich materials, i.e., CRMs such as NIST 1400 (Bone Ash), CTA-AC-1 (Apatite Concentrate Kola Peninsula) and NCS DC70308 (Carbonate Rock), and six natural samples, such as a dolomite, a phosphate rock, an enriched superphosphate fertilizer, pork bones, pork bones after incineration, and after steam gasification.

The applicability of the hydride generation (HG) sample introduction technique combined with different spectrochemical detection methods for non-chromatographic speciation of toxic As species, i.e., As(III), As(V), dimethylarsinate (DMA) and monomethylarsonate (MMA), in waters and other environmental, food and biological matrices is presented as a promising tool to speciate As by obviating chromatographic separation. Different non-chromatographic procedures along with speciation protocols reported in the literature over the past 20 year are summarized. Basic rules ensuring species selective generation of the corresponding hydrides are presented in detail. Common strategies and alternative approaches are highlighted. Aspects of proper sample preparation before analysis and the selection of adequate strategies for speciation purposes are emphasized.

Commercially bottled birch saps (BSs) were analyzed for several nutrient (Ca, Cu, Fe, Mg, and Zn) and toxic (As, Cd, Ni, and Pb) elements using inductively coupled plasma optical emission spectrometry (ICP OES). The method was validated under the conditions of several sample preparation procedures, including a traditional digestion as well as alternative non-digestion schemes. It was found that the direct analysis of untreated BSs gives the best results, i.e., limits of detection at 0.02−5.8 ng mL−1, precision better than 5%, accuracy from 98.0% to 104.5% and determination of 12 elements in a short time (~1 min per sample). The multi-element analysis of nine commercially available bottled BSs showed that they contained mainly Mg and Ca, small quantities of Mn, Zn, Cu, and Fe, but are free from toxic elements such as As, Cd, Ni, and Pb. Additionally, the nutritional value of BSs was examined using in vitro gastro-intestinal digestion (GID) to determine the bioaccessible fraction of elements. Accordingly, bioaccessibility of nutritious ones (Ca, Cu, Fe, Mg, Zn) was

A new simple and rapid method for the determination of the total concentrations of Cu, Fe, Mn, and Zn in beetroot juices by flame atomic absorption spectrometry was developed and validated. The method included a very simple sample preparation, i.e., the two-fold dilution and acidification of the samples with HNO3 to 1 mol·L−1 and provided the precision within 2−3% and the trueness better than 6%. The method was applied for the rapid screening analysis of the different commercially available beetroot juices. The chemical fractionation of Cu, Fe, Mn, and Zn was also proposed by the two-column solid-phase extraction with the reversed-phase and cation exchange tubes. It was revealed that Cu, Fe, Mn, and Zn were primarily in beetroot juices in the form of the organically bound forms, contributing to the distinguished hydrophobic and residual fractions. The sums of the mean contributions of both fractions were up to 98% (Cu, Fe, Zn) and 100% (Mn), pointing out that no labile nor unbound forms of the studied metals were present in the matrix of beetroot juices.